Electric switch.



E. E. CLEMENT.

ELECTRIC SWITCH.

APPLICATION FILED JUNE 29,1910.

1,107,153. Patented Aug. 11, 1911 2 SHEETS-SHEET 1.

ma IIIIIIIIIIIIIIIIII @uwntoe E. E. CLEMENT.

ELECTRIC SWITCH.

APPLICATION FILED Jun 29, 1910.

Patented Aug. 11,1914.

2 BHEET$SKEET 2.

3n uentov UNITED STATES PATENT OFFICE.

ED'WARD E. (ELEMENT, OF WASHINGTON, DISTRICT OF COLUMBIA.

ELECTRIC SWITCH.

bia, have invented certain new and useful Improvements in Electric Switches, of which thefifollowing is a specification, reference being. had therein to the accompanying drawin My invention relates to electric switches and has for its object the production of a simplified form of a selective step by step switch having multiple arms and bank contacts arranged in the segment of the circle instead of in a complete circle; whereby the contents are made accessible and the bank is rendered open, without loss of continuity in action; I

This application is a division of my prior application, Serial No. 556.213, filed April 18, 1910, as to the disclosure in Figures 1 to 4 inclusive; and as to the disclosure in Fig. a division of my prior application, Serial No. 383,875, filed July 15, 1907, wherein is specifically disclosed a bank of contacts arranged in the arc of a circle, a spindle, and a plurality of connected wiper arms (three) mounted on said spindle and spaced apart thereon at angular distances representing the same fraction of a circle (120) as the angular length of the arc of contacts, whereby by rotating the spindle, continuous engagement may be had between the wiper arms and the bank contacts, yetwith only one arm engaging the contacts at a time. The specific construction of the operating means for the wiper arms is on the other hand the same as that disclosed in Figs. 1 to 4-, and a division of Serial No. 556,213 as aforesaid.

1 llyinvention is illustrated in the accomng drawings in which" 1 is a plan view of the switch, Fig. 2 is a side view thereof, Fig. 3 is a face View of part of a bank removed. Fig. -'l is an end view of the switch. Fig. 5 is a plan view of a modification.

Referring to the drawings. the switch is Specification of Letters Patent.

Original applications filed July 15, 1907. Serial No. 383,875, and April 18. 1910, Serial No. 556,213.

and this application filed June 29, 1910.

j electromagnet.

in the set screws 5".

Patented An 11, 191i.

Divided Serial No. 569,606.

Fig. 3 shows part of a bank removed from the switch which is accomplished by taking out the screws 8* which fasten the ears 8* to the posts a constituting extensions of the frame upon which the magnet unit a is likewise mounted by means of screws s".

The spindle s is rotated by means of a ratchet wheel 8 engaged by a pawl a carried upon the end of the aluminum armature lever e which is secured at the other end to-the iron armature s of the The lever s is formed of aluminum in a hollow shape for stiffening purposes and at the armature end is provided with 'a right angle extension 8 having lateral wings s overlapping the iron armature s and riveted thereto. The armature is transversely scored at s to. receive a knife edge a which is given a sliding ad= iustment by providing it with slots working Outside of the knife edge a pair of coiled springs s is provided, each secured at one end to an ear 8 formed on the i'rame and the other end passing over the shank of a screw s'-" whose head is held by an ear s "forming an extension'ot one of the wings a. By turning the screws s", the tension of the springs maybe adjusted.

It should be understood that the magnet .9 comprises a pair of cores arranged side by side and parallel to each other. These cores are united at their rear ends by an iron yoke s and when energized act jointly upon the iron armature s. \Vhen current flows through the windings and the armature is attracted the lever arm .9 is thrown to the left in Fig. l, forces the pawl 8 into one of the teeth of the ratchet wheel .9 rotating the wiper s in the direction oi the arrow. At the end of one step a positive stop is furnished by a heel piece 8 on the pawl coming in contact with the frame. The toe of the pawl is kept pressed into engagement with the ratchet by means of a short spring 8 It will be observed that the wiper arm is double, and upon close examination of Fig. 1 it will be found that one arm a comes upon the first contact justas the other arm 5 is leaving the last contact. This arrangement permits the contact bank to be made open or in the arc of a circle instead of a complete circle, which latter would have to be employed if only a single wiper arm were available. Such a multiple wiper to permit set 120 apart. The contact bank in this case extends through a little less than 120, or one-third of a. circle. The effect is the same as above described, that is to say each wiper arm will leave the last contact in the bank just as its successor comes on the first contact, thereby giving a continuous test with an open bank.

Having thus described my invention what I claim and desire to secure by Letters Patent is- 1. An electric switch comprising a frame,-

a bank of contacts in the arc of a circle with interposed insulation mounted in said frame, wipers pivoted on the frame so as to sweep over the contacts, a ratchet wheel connected with the wipers,'and an electromagnetic unit for driving the ratchet comprising an iron core end-supported on the frame with its axis extending toward the axis of the wipers, a winding on the core, a fixed bearing near the free end of the core, an iron armature adapted to rock on said bearing and extending into proximity to said free end of the core as a pole piece, a relatively light lever struck from sheet material connected at one end to said armature and extending along the magnet substantially parallel to the core into iroxiinity to the wiper ratchet, and a pawl pivoted in the end of the lever and engaging the ratchet, said lever and armature together constituting a bell crank and the lever being formed up with a hollow rib in its body extending beyond and around its junction with the armature so as to stiffen the structure and prevent springing or flexing in the plane of its motion. 7

2. An electric switch comprising a frame, a bank of contacts in the are of a circle with interposed insulation mounted in said frame, wipers pivoted on the frame so .as to sweep over the contacts, a ratchet wheel connected with the. wipers, and an electromagnetic unit for driving the ratehet'comprising an iron core supportedon the frame from one end and having its other end projecting laterally therefrom, a winding on the core, a fixed bearing near the free end of the core, an iron armature adapted to rock on said bearing and extending into proximity to said free end of the core as a pole piece, a lever formed of light nonmagnetic material connected at one endto said armature and extending along the magnet substantially par"- Uopiesof this patent may be obtained for five cents, each, by addressing the allel to the core into proximity to the wiper ratchet, and a pawl pivoted in the end of the lever and engaging said ratchet, said lever and armature together constituting; a bell crank, and the lever being provided with stlffening means at its juncture with the armature to prevent springing or flexing in the plane of its'motion.

3. An electric switch comprising bank contacts, a coiiperating wiper and means for driving the same, together with a control magnet nmt therefor composed of the following instrumentalitios': a pair of parallel cores 8 carrying windings s and united by a yoke 8 a frame or return bar extending parallel to the magnet cores and carrying a knife edge extending transversely to and overlying the free ends of the cores, an iron armature engaging said knife edge and extending across the core-ends, a lever of light non-magnetic material formed in bell crank shape with a stiffening rib around its angle, its short member being secured to the iron armature and its long member extending parallel to the cores into operative proximity to the wiper actuating means, and a pair of symmetrically disposed coiled springs each secured at one end to the yoke end of the magnet structure and at the other end to a projection on the armature outside of the point of attachment of the lever, both of said springs being normally under tension and acting to withdraw the armature from the pole pieces and to maintain said armature in constant engagement with the knife edge.

t. An electric switch comprising an open bank of contacts formed in the arc of a circle, and a double wiper arm having contacts at both ends adapted-to be rotated in contin nous engagement with said bank contacts, but with only one end engaging at the same time.

5. An electric switch comprising a bank of contacts arranged in the are of a circle, 05 a spindle, and a plurality of connected wiper arms mounted on said spindle and spaced apart thereon at angular distances representing the same fraction of a circle as the angular length of the arc of-contacts, whereby iii rotating the spindle, continuous engagement may be maintained between the wiper arms and the bank-contacts, only one arm engaging the contacts at the same time however.

In testimony whereof I afiix my signature in presence of two witnesses.

EDWARD E. CLEMENT.

Witnesses:

THOMAS DURANT, H. H. Lownnsrein.

G ommissioner of Patents,

Washington, I). G. 

